U0243low severityNetwork
Lost Communication with Trailer Hitch Module
on 2008 Audi S5 4.2L V8 · AWD
What this code means
Cannot communicate with the integrated trailer hitch control module.
Symptoms
- Trailer lights not working
- Trailer brake output disabled
- Tow/haul mode limited
- Trailer sway control disabled
Common causes
- Hitch module failure
- CAN bus wiring
- Module power loss
- Fuse blown
- Trailer connector corrosion
Diagnostic steps
- Check hitch module fuse
- Test power and ground
- Check CAN wiring
- Inspect trailer connector
- Test trailer light outputs
Repair notes
Check fuses and trailer connector. Corrosion at trailer plug is the most common cause.
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Other Network codes on this vehicle
00003
Control Module - Defective
01304
Radio - No Communication
01312
Powertrain Data Bus - Defective
01314
Engine Control Module (ECM) - no communications
01315
Transmission Control Module (TCM) - No Communication
01316
ABS Control Module - No Communication
01317
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01318
Immobilizer Control Module - No Communication
01321
Airbag Control Module - No Communication
U0001
High Speed CAN Communication Bus